Jewish Genes and Anti-Semitism

Some worry that the discovery of "Jewish" genetic diseases will negatively affect the image and treatment of Jews.

A new look at Tay‑Sachs blood samples, in fact, revealed that Ashkenazim have elevated levels of certain mutations linked to breast cancer. But no reputable figure suggests that Jews carry any more disease genes than anyone else.

Sickle cell mutations, for example, occur disproportionately in people of African descent, cystic fibrosis mutations in northern Europeans, thalassemia mutations among Greeks and Italians in its alpha form and among East Asians in its beta form, and hemophilia mutations in the Russian imperial family. A number of rare genetic diseases afflict the Amish, and diabetes occurs extremely commonly in certain Native American peoples.

And we are only at the beginning of understanding what else lurks in people’s genes. It doesn’t take Gregor Mendel to figure out that inbred populations have high concentrations of particular genes. And since eschewing marriage with outsiders has ranked among important Jewish values at least since the early rabbinic period (though not, interestingly, in biblical times, when everyone from King Solomon to Naomi’s sons eagerly wed neighboring peoples), 30 or more generations of marrying fellow Ashkenazim have produced a distinctive gene pool.

But still, many Jews say, “Us again?” when they read of a new “Jewish” gene. The Post quotes National Cancer Institute epidemiologist Patricia Hartge, who points out that “it could have been the Icelanders, the Finns, or anyone else you might be studying.” And in fact, Iceland’s small, island‑bound population does have its own characteristic breast cancer mutation of the BRCA‑2 gene. But Jewish geography may also play a special role in the high rate of “Jewish” discoveries.

Ashkenazim are over‑represented among the nation’s medical researchers. Bert Vogelstein of Johns Hopkins, for example, discovered the new “Jewish” colon cancer mutation because he recognized that two men who carried it were both Jews. Vogelstein’s own Ashkenazi background undoubtedly helped him make a potentially life‑saving connection that a non-Jew might have missed.

I, for example, have a friend of Finnish descent. Certain details of her appearance, name, and cultural background probably shout her ethnic identity to fellow Finns, but they mean absolutely nothing to me. I wouldn’t have known that she belongs to that small, long‑isolated, and genetically and linguistically distinctive people unless she told me. And neither, presumably, would a medical researcher of non‑Finnish background.

But even as information on more and more “Jewish” genes accumulates, they’re not going to stay Jewish for very long. With increasing intermarriage, our gene pool is becoming more like other peoples. Our genes become theirs, and theirs ours.

These days, the Jewish child of, say, one Ashkenazi and one African-American parent might carry a sickle cell gene, while the non‑Jewish child of an Ashkenazi parent and his or her WASP or Irish or Chinese or Peruvian spouse might carry one or more of the erstwhile “Jewish” genes.